What may be even more important is that the device took away the constant monitoring that's required with type 1 diabetes.

"It's difficult for people who don't live with type 1 diabetes to understand how much work it is. It's such a burden. But, everyone in the trial said that burden was all lifted. The device is inherently automated -- it's diabetes without the numbers," said study senior author Edward Damiano, an associate professor in the department of biomedical engineering at Boston University. Damiano understands the issue more keenly than most, as he is the father of a 15-year-old son with type 1 diabetes.

Damiano said the device "exceeded our expectations, reducing average [blood-sugar levels] to what's well below standard-care therapy, while at the same time reducing [low blood-sugar levels]."

Type 1 diabetes is an autoimmune disease caused by a mistaken attack on healthy insulin-producing cells in the body, destroying them. Insulin is a hormone necessary for ushering sugar into cells to provide fuel for those cells. People with type 1 must replace the insulin their bodies no longer produce through injections or through a tiny catheter attached to an insulin pump.

However, figuring out exactly how much insulin to give is no easy task. Both too much insulin and too little insulin can have dangerous, even deadly, consequences.

Here's how the bionic pancreas can help. It contains two hormones -- insulin and glucagon. Insulin lowers blood sugar and glucagon can raise blood sugar quickly. The current version of the bionic pancreas had two insulin pumps -- one that delivered small doses of insulin and the second for glucagon. The device also included a smartphone with an app that contained the computer program to control the pumps. The phone also wirelessly communicated with a continuous glucose monitor that constantly reported blood sugar levels.